Feline interferon and process for production thereof

Abstract

A recombinant silkworm nuclear polyhedrosis virus containing DNA coding for a protein of feline interferon; the recombinant virus is constructed by cotransfection a recombinant plasmid having a gene coding for a protein of feline interferon and a silkworm nuclear polyhedrosis virus DNA into established silkworm cells, and cloning the desired recombinant virus. The recombinant virus is useful for a mass-production of feline interferon.

We claim: 
     
       1. A process for production of a recombinant silkworm nuclear polyhedrosis virus constructed by a gene recombination of DNA coding for a protein of feline interferon and a silkworm polyhedrosis virus, comprising the steps of: cotransfecting a recombinant plasmid having a gene coding for a protein of feline interferon and a silkworm nuclear polyhedrosis virus DNA into established silkworm cells; and   cloning the desired recombinant virus.   
     
     
       2. A process according to claim 1, wherein the plasmid is selected from the group consisting of pBmFeIFN1, pBmFeIFN2-1, pBmFeIFN2-2, pBmFeIFN2-3, and pYU871. 
     
     
       3. A process according to claim 1, wherein the established silkworm cell is a BM-N cell. 
     
     
       4. A process according to claim 1, wherein said recombinant plasmid is a plasmid which comprises the BglI-HincII restriction fragment of plasmid pFeIFN1 which includes DNA encoding the Feline Interferon protein ligated into a plasmid suitable for the expression of Feline Interferon in insect cells. 
     
     
       5. A process according to claim 4, wherein said recombinant plasmid is a plasmid which further comprises the BglI-HincII restriction fragment of plasmid pFeIFN1 which includes DNA encoding the Feline Interferon protein ligated to a linker, ##STR2## which attaches tot he BfglI end of the BglI-HincII restriction fragment. 
     
     
       6. A process according to claim 1, wherein said recombinant plasmid is a plasmid which comprises the EcoO109I-HincII restriction fragment of plasmid PFeIFN1 which includes DNA encoding the Feline Interferon protein ligated to the linker ##STR3## 
     
     
       7. A process according to claim 6, wherein said recombinant plasmid is a plasmid which further comprises the small SfaNI-BglI fragment which is upstream of the FeIFN coding region of plasmid PFeIFN1, as shown in FIG. 5, ligated to the BglII site of the linker DNA so as to form a segment of DNA bounded by a BamHI site and HincII site which contains the nucleotides encoding the Feline Interferon protein. 
     
     
       8. A process according to claim 7, wherein the BAmHI-HincII fragment containing the nucleotides encoding the Feline Interferon protein is ligated to a plasmid suitable for expression of Feline Interferon in insect cells. 
     
     
       9. A process according to claim 8, wherein the said plasmid suitable for expression of Feline Interferon in insect cells is the plasmid PBM030. 
     
     
       10. A recombinant silkworm nuclear polyhedrosis virus according to claim 5, which is BMFeIFN1. 
     
     
       11. A recombinant silkworm nuclear polyhedrosis virus according to claim 5, which is BmFeIFN2-1. 
     
     
       12. A recombinant silkworm nuclear polyhedrosis virus according to claim 5, which is BmFeIFN2-2. 
     
     
       13. A recombinant silkworm nuclear polyhedrosis virus according to claim 5, which is BmFeIFN2-3. 
     
     
       14. A recombinant silkworm nuclear polyhedrosis virus according to claim 5, which is rBNV100. 
     
     
       15. A recombinant silkworm nuclear polyhedrosis virus containing a DNA coding for a protein of feline interferon. 
     
     
       16. A recombinant silkworm nuclear polyhedrosis virus selected from the group consisting of BmFeIFN1 (ECACC V89062701), BmFeIFN2-1, BmFeIFN2-2, BmFeIFN2-3, and rBNV100.